Weak or missing academic use of sources can lead people to mistake lies or rumours for scientific truth. This junk science can persist for decades, and can become an element of our general common knowledge.

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Perhaps best known is the spinach myth.

The notion that spinach is a good nutritional source of iron stems from a 1930s reference to a German analysis made in the 1890s. It was reinforced by the comic strip and cartoon character “Popeye”, who has also been seen to be eating spinach since the 1930s for super strength.

Although years have passed since the spinach/iron myth was disproven, it continues to live on.

As does the story about how this myth got started. The claim has been made in the scientific literature that the vegetable's iron content was accidently increased tenfold when German chemists misplaced a decimal point.

This spectacular error of a decimal point that tricked the world into eating more spinach has been referred to for decades. But then in 2010, Mike Sutton, a criminologist at Nottingham Trent University, started doing some detective work by searching for the primary source. He showed that the entire story had no supporting documentation and that the decimal point error was just another academic myth.

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(Never knew about this spinach myth and of all the veggies I do like spinach. But I hardly any veggies anyway.)